''I've actually been pretty sick lately - I've been having like a bug,'' she said after the match that lasted 2 hours, 15 minutes on the green clay at the Family Circle Tennis Center. ''You just have to play your way into the week and just continue to feel better.''

The seven-time Grand Slam champion has battled injuries and Sjogren's syndrome, a fatigue-causing autoimmune disease, during the past two years.

''I haven't gotten rid of it. I wish I could have. Unfortunately it just clings to me,'' Williams said. ''I've just learned to handle it mentally and also I try to do things all the time, just always going for optimal health.''

Top-ranked Serena Williams plays Tuesday night against 78th-ranked Jana Cepelova of Slovakia. She is aiming for her second straight title and third this year after winning a record seventh Sony Open last weekend

Venus Williams seemed in control of the match going up 6-3 in the first set and surrendering only two points in her last two service games.

But the 56th-ranked Zahlavova Strycova rattled off seven straight games to shut out the 28th-ranked Williams in the second set and go up 1-0 in the third.

Williams rallied for a 5-4 lead in the third set, but Zahlavova Strycova fought off four match points to win the game and tie the set at 5-all. Williams broke serve in the next game - helped by a final point double-fault - and held serve at love to win the match.

Williams staved off what could have been her earliest exit at the Family Circle. She's making her seventh appearance at the tournament she won a decade ago. Williams, who won the Dubai title this year, said she didn't get down on herself after dropping the second set.

''My gosh, if you are careful and you don't play almost perfectly, every single player is so talented out here that you can drop a set or the match,'' Williams said. ''So its stay focused, really believing in yourself and taking some chances and making your shots.''

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